Without limiting the scope of the invention, its background is described in connection with RF device packaging, as an example.
Heretofore, in this field, packages operating at frequencies of 1 GHz or higher were normally of metal-ceramic construction, or metal bases with plastic cavity lids and metal leads sticking through the plastic sides.
Standard SO8, SO14, and SO20 plastic encapsulated packages have been used for RF applications at frequencies up to 1 Ghz. However, these leadframes have high lead inductances which must be accounted for in the design of the ICs inserted into the leadframes. Isolation between leads is also low, typically 20 Db or less at 1 Ghz. This limits the amount of amplifier gain which can be inserted in the packages at microwave frequencies, and creates the potential for coupling problems between RF ports and RF and DC ports.